German investigators doubt bus attack was work of radical Islamists
After multiple explosions struck Borussia Dortmund's team bus Tuesday, German investigators expressed doubt Friday that radical Islamists were responsible for the attack.
Three identical letters that read "in the name of Allah" found near the scene may have been an attempt to trick the police and public into thinking there was an Islamist motive, according to BBC News.
"As of now, all infidel actors, singers, athletes, and all prominent personalities in Germany and other crusader nations are on a death list of the Islamic State," the letters read. The letters also apparently claimed responsibility for the Berlin Christmas market attack that killed 12.
Related: Man detained over Dortmund bus blasts a suspected ISIS member
Investigators said the attack may have been the work of left- or right-wing political extremists or violent football supporters, and noted the explosives were professionally made devices featuring elements consistent with military expertise.
An Iraqi national suspected of having Islamic State (IS) ties was detained Wednesday and later arrested with the consent of a German judge.
Two national broadcasters, NDR and WDR, in conjunction with German newspaper Suddeutsche Zeitung, reported Friday that the letters could be fakes.
State prosecutor Frauke Koehler called the reports "accurate" when asked for comment. He noted that several elements of the letters were "untypical" for groups like the IS, including claims that public figures and athletes were at risk unless the Ramstein Air Base is closed and warplanes withdrew from Syria.
The terrorist group does not negotiate in such a way, Koehler explained.
Anonymous security professionals also told Suddeutsche Zeitung the letters seem likely to have been written by a native German speaker who added errors to give the impression that the author was less fluent in the language.
A second German paper, Tagesspiegel, said it received an email from a right-wing sender who characterized the attack as a warning and added racist threats. That newspaper reports investigators are taking the email seriously.